MARKERS OF BONE METABOLISM AND MINERAL BONE DENSITY IN PATIENTS ON RENAL REPLACEMENT THERAPY BY PERITONEAL DIALYSIS

Lesovoy V. N., Andonieva N. M., Valkovskaya T. L.

CLINICAL AND EXPERIMENTAL MEDICINE

Scentific article

Modern methods of renal replacement therapy (RRT) can significantly extend the life of patients with end-stage renal disease (ESRD). However, the increase in the life expectancy of these patients is associated with the formation of new medical problems, one of which is a change in bone mineral density (BMD), as a result of impaired bone metabolism. In recent years, much attention has been paid to the study of BMD in this category of patients. The histomorphology of the iliac crest biopsy is central to the diagnosis of bone disorders in dialysis patients. However, the invasiveness and relative difficulty of performing this manipulation necessitates the use of other diagnostic criteria for renal osteodystrophy. Along with the determination of parathyroid hormone (PTH), calcium (Ca), phosphorus (P) and alkaline phosphatase levels, osteopontin (OP), a pleiotropic cytokine that is expressed in mineralized tissues and is the main bone-free collagen matrix protein, is of considerable interest. The aim of the work is to study markers of bone metabolism in patients with ESRD on replacement therapy by peritoneal dialysis. The object and methods of research. The study included 46 patients who received replacement therapy by peritoneal dialysis. Bone mineral density, calcium, phosphorus, alkaline phosphatase, parathyroid hormone and osteopontin levels were determined in all patients. Results and consideration. In determining the BMD, osteoporosis was detected in 17 patients, osteopenia in 15 and normal bone density in 14 patients. The level of calcium was approximately same in patients regardless of BMD and was within the normal range. The level of inorganic phosphorus was increased in all patients by an average of two times. In dialysis patients it is necessary to maintain the level of parathyroid hormone in the range of 150-600 pg/ml. The PTH level of most patients (65%) was within the range of 150-600 pg/ml and averaged 445 ± 24 pg/ml, in 12 patients (25%) it exceeded 600 pg/ml and was 1175 ± 368 pg/ml. The average level of osteopontin in patients on peritoneal dialysis was 6-9 times higher than the reference values and was –248, 31 ± 45.3. According to our data, only in 30.4% of patients on dialysis, the OP level was within the normal range for a healthy population. In patients with normal BMD, the average level of parathyroid hormone was 238 ± 28.7 pg/ml, the level of osteopontin – 104.5 ± 78 ng/ml. In patients with reduced bone mineral density, the level of PTH was 745 ± 64.45 pg/ ml, the OP level – 246 ± 50.31 ng/ml. Conclusions 1. The ESRD is associated with a decrease in BMD, which is confirmed by ultrasound densitometry data. Only 30% of patients had normal BMD. In 32% of patients was observed osteopenia, in 38% – osteoporosis. 2. The identified statistically significant correlations of the OP level and osteodensitometry indicators indicate that this marker can be used to determine the degree of bone resorption. 3. Peripheral densitometry is a sensitive and informative method for the early diagnosis of osteopenic syndrome in patients with ESRD.

chronic kidney disease, bone metabolism, osteodensitometry, osteopontin, end stage of renal disease, peritoneal dialysis

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«Bulletin of problems biology and medicine» Issue 1 Part 1 (148), 2019 year, 137-140 pages, index UDK 616.71-008.82:577.118:616.61-78

10.29254/2077-4214-2019-1-1-148-137-140